session 1, unit 1 course overview. introduction course – env 7335 air quality modeling instructor...

Session 1, Unit 1

Course Overview

Introduction

Course – ENV 7335Air Quality ModelingInstructor – Yousheng Zeng, Ph.D., P.E.Prerequisite – ENV 7331 or equivalent www.seas.smu.edu/env/7331

Course Objectives

Understand air pollution meteorology and theory of atmospheric dispersion modelingBe able to perform an air quality modeling analysis using the most common regulatory model – ISC3 Understand the regulatory requirements related to air quality modeling analysis Become knowledgeable of other air quality models

Course Materials

Textbook – “Atmospheric Dispersion Modeling Compliance Guide” with CD-ROMby Schnelle & DeyMcGraw Hill, 1999Other materials available on the Internet ISC3 Program and Manual BPIP Program and Manual Other relevant information

Course Outline

Session 1 Introduction/Course overview Basic meteorological principles

Session 2 Air pollution climatology Turbulence and the mixing process

Session 3 The dispersion model Dispersion coefficients

Course Outline

Session 4 Plume rise The effect of averaging time, multiple sources,

and receptors

Session 5 Modeling in the presence of dispersion ceilings SCREEN3, ISCPC, and midterm review

Session 6 Chimney, building, and terrain effects Midterm exam

Course Outline

Session 7 Chimney design The ISC3 Model

Session 8 ISC3 practical issues and the BPIP program Regulatory procedures and PSD modeling

Session 9 Other important models – ISC-PRIME,

AERMOD, CALPUFF, UAM, CAMx Final review

Course Outline

Session 10 Modeling accidental releases Final exam Modeling exercise due Modeling project report due

Course Work

Study problems at the end of each chapter in the textbookModeling exercise use the ISCPC model in the textbook CD-ROM 20 practice problems in Appendix E Earn credit by turning in answers for 10 of

them (even or odd numbers) to demonstrate completion of the exercise

Midterm examFinal exam

Course Work

Modeling Project EPA ISCST3 model and BPIP program Multiple sources Buildings and terrain Receptor grid 1 year met data Modeling report

Grading

Midterm exam 20 points

Final exam 30 points

Modeling exercise 10 points

Modeling Project 40 points

Total 100 points

Communication

Course website:www.seas.smu.edu/env/7335All students should send me a short email at yz@wisedom.net so that I can distribute announcement/materials if necessary

Session 1, Unit 2

Basic meteorological principles

Atmosphere

Composition Near surface (tropospheric air)

Nitrogen: 78.08% Oxygen: 20.95% Argon: 0.9% Contributors to atmospheric absorptive properties

H2O: Variable CO2: 332 ppm CH4: 1.65 ppm N2O: 0.33 ppm O3: 0.01-0.1 ppm

Atmosphere

Vertical temperature profile Troposphere Stratosphere Mesosphere Thermosphere

Energy Balance

Radiation Occurs when an electron drops to a lower

level of energy Blackbody radiation

Emissivity of a blackbody at 6000 K (the sun) Emissivity of a blackbody at 300 K (the earth)

Energy balance Day vs. night Local energy balance/out of balance Global energy balance

Greenhouse effect

Scales of Atmospheric Motion

MicroscaleMesoscaleSynoptic (cyclonic scale)Macroscale

General Circulation

General energy balance controls large scale air movementAir circulation if the earth did not turnGeneral circulation Rotation of the earth – Coriolis force General circulation pattern

Geostrophic Layer

500-1000 m heightTwo forces Horizontal pressure gradient Coriolis force

Undisturbed constant air flow – Geostrophic wind

Planetary Boundary Layer

Surface to 500 m highThree forces Horizontal pressure gradient Coriolis force Frictional force due to earth’s surface roughness

Different wind from geostrophic wind Speed – retarded by friction Direction – altered due to force balance

Urban/mountain vs. smooth surfaceSurface layer – from surface to 50 m high

Impact of Fixed Geographic Features

Sea breezeValley windDrainage windFlow patterns due to topographical features